A259087 - OEIS

A259087

Number of n-celled polyominoes which are of rectangular but not square type.

0, 1, 1, 4, 6, 28, 83, 289, 1030, 3860, 14154, 53222, 202001, 771255, 2945803, 11304541, 43564276, 168413249, 652292925, 2531493604, 9845752518, 38372748112

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

Table of n, a(n) for n=1..22.

T. R. Parkin, L. J. Lander, and D. R. Parkin, Polyomino Enumeration Results, presented at SIAM Fall Meeting, 1967, and accompanying letter from T. J. Lander (annotated scanned copy). See page 21. The 15th entry is not included because their value for A000105(15) was incorrect.

FORMULA

a(n)+A259088(n) = A000105(n).

CROSSREFS

Cf. A259088, A000105.

Sequence in context: A122113 A093815 A142859 * A364737 A056221 A046849

Adjacent sequences: A259084 A259085 A259086 * A259088 A259089 A259090

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Jun 18 2015

EXTENSIONS

a(15)-a(17) computed from A000105-A259088 by Jean-François Alcover, Dec 30 2019

a(18)-a(22) from John Mason, Nov 19 2021

STATUS

approved